Hybrids and fertility

From: Derek Glidden (dglidden@geocities.com)
Date: Wed Sep 03 1997 - 13:21:01 PDT


Date: Wed, 03 Sep 1997 16:21:01 -0400
From: Derek Glidden <dglidden@geocities.com>
To: cp@opus.hpl.hp.com
Message-Id: <aabcdefg3350$foo@default>
Subject: Hybrids and fertility

I keep hearing/reading about various CP hybrid species not being fertile
either self- or cross-. I'm not sure I understand why? For one thing,
I thought (obiously wrongly) that species were only fertile to the same
species, so I guess I don't understand how hybrids can be developed
anyway. I've always been under the impression that a "hybrid" was a
cross between two differing _variations_ in a distinct species. At
least, that's what I've thought about, say, a new rose hybrid, or maybe,
since I'm in Florida, a new strain of citrus tree. So, if you can cross
differing species, then, since you have a "valid" genetic combination,
why does it seem that so many of them are sterile? I would expect that
any valid genetic combination should be able to reproduce.

And I suppose, along similar lines, since Nepenthes are male/female
differentiated, does it make any difference to your hybrid which sex of
which species you're crossing? (i.e. is a Male mirabilis x Female
gracilis the same thing as a Female mirabilis x Male gracilis? I'm just
pulling species names that I can think of, I don't know if that's even a
valid cross...) Or is there no difference at the genetic level, but the
common naming is different to differentiate the two?

I guess this is really kind of a Genetics 101 question, but I can't
figure it out. Of course, there's that whole thing with horses and
donkeys that I never understood either...

-- 
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Derek Glidden                       http://www.illusionary.com
Illusionary.com                Home of the Pagan Resource Site
   Web development, database, graphics and general plumbing
Linux, FreeBSD, Apache, MySQL, PostgreSQL, PHP (Say No to NT!)



This archive was generated by hypermail 2b30 : Tue Jan 02 2001 - 17:31:09 PST